A few weeks ago this was one of the Inquisitor clues:
Case involving former taxmen is cloudy (7)
The theme of the puzzle meant that several clues included the letters RAT, and I worked out that it was likely to be IR (Inland Revenue) inside CRATE (case), giving CIRRATE. I knew about "cirrus" clouds so guessed that CIRRATE probably meant "cloudy", and entered it. It turned out to be correct and I thought no more of it at the time.
But CIRRATE doesn't mean "cloudy". It's a biological term meaning "equipped with a cirrus", or tentacle. The adjective corresponding to cirrus clouds is "cirrous" or "cirrose" (either of which can confusingly also mean the same as CIRRATE). I have checked in multiple sources, including the OED Online, and can find no suggestion that CIRRATE is related to cirrus clouds.
This isn't the first time I've seen questionable definitions in the Inquisitor, yet no one ever seems to comment on them - indeed one solver on Fifteensquared said that CIRRATE was one of his first answers in. How does this sort of stuff get through the editorial process, and why don't solvers seem to spot it?